Many surgical procedures concern the temporary or permanent insertion, into the soft or bony tissue of a patient, of prosthetic and other artificial devices that are required to fit the anatomy of the patient to a very high degree of precision and accuracy. One such application concerns implant dentistry, in the course of which one or more implants are surgically placed within the jawbone of a patient, to receive and support prosthetics, e.g., complete restoration, designed to simulate and replace one or more natural teeth lost by the patient. It is well known that, to be wholly successful, implant procedures must adhere to very strict placement, orientation and sizing requirements determined by existing bone structure and dentition, whereby the prosthetics to be fitted onto surgically-placed implants must be preferably designed, shaped and sized specifically to conform to the precise anatomical geometry of the patient, including the location, shape and size of adjoining teeth, and must transition to the precise orientation of the principal axis of the supporting implant with a high degree of accuracy.
Conventional methods for meeting these rigorous requirements provide for the creation of a model of the patient's jaw and dentition, the making of a model comprising the taking of a so-called “impression” of the patient's dentition, using a malleable substance placed over and around the teeth in the patient's mouth comprising the entire dental arch. Typically this impression is taken following the surgical insertion of the implant. Typically, reference components called impression copings are affixed to the external extremity of the inserted implant, and serve to reference the location and angular orientation of the implants. Subsequently, a model made from a mold based on the impression will incorporate so-called “analog” implants to model the implants in the patient's jaw, and prosthetic devices for the implants will be designed and manufactured based on the geometry of the model created as described.
In actual practice the conventional procedure described above is fraught with numerous difficulties and shortcomings. It has proven impossible for dental practitioners to make dental impressions, and thus models, that are consistently free of dimensional and positional errors. In recent years, efforts have been made to employ image-based modeling techniques to address these well-known problems of conventional implant dentistry procedures. For example, two-dimensional (2D) and three-dimensional (3D) digital image technology has been tapped as a tool to assist in dental and orthodontic treatment. In these efforts, images are taken of the patient's mouth, and a three-dimensional image is used to assist in dental treatments. The particular demands for great accuracy, however, have thus far resulted in the absence of acceptable three-dimensional imaging techniques in the field of dentistry that can result in an accurately formed prosthesis and/or complete restoration.